Hrm hrm hrm...things to do for a long college break. Let's see, what did I do?
Books--read books! Pick an especially long series and power your way through it. Then it'll take a lot of time whether or not you're a fast or slow reader.
Art--Pick some art form you're not used to and just give it a whirl! Photography works if you have a camera. You could also do painting, ceramics, woodworking, something with textiles, writing, etc etc. I'd avoid metal-related ones just because they can be expensive though (took a jewelery class once; it demolished my wallet). You can look up some guides and stuff online to give it a shot but don't be afraid to just experiment.
Walking/Sport/Etc -- I personally try and take a walk once a day if I'm not at work or something. I bring some music with me and it's a great way to just organize my thoughts and plan stuff out, for my real-life troubles or for something like writing, to come up with ideas. You might have a local gym in the area too; you could always go work out, or see if they have a short term class for yoga or martial arts or something that you can try out. You might find a new hobby to continue through school, PLUS it'll be healthy for you
Part-time job -- Some places might just need seasonal help. This could always bring in the money and ease a load off those school bills.
Find a Different Game -- I did this a lot actually XD I'd get tired of WoW, so I'd pull out my ol' Gamecube or my even older Playstation and indulge in a little nostalgia with some classic Final Fantasies or Mario games. It was actually really fun!
Hope there is something here that appeals XD
~VelkynKarma